This invention relates generally to papermachines through which a paper web is routed and relates, more particularly, to means and methods for cleaning the surface of a papermachine component begrimed with pitch or other contaminates collected from a paper web as the web moves around the surface of the component. Examples of such components include the cylindrical rolls located in the pickup section of a papermachine as well as the synthetic belts and fabrics which engage the paper web in the press section of a papermachine.
Heretofore, the grimy, wet surface of a cylindrical roll of a papermachine has been mechanically cleaned with a doctor blade which is supported adjacent the surface of the roll. To this end, doctor blades of the prior art commonly include a hard (commonly steel) wiper tip which is maintained in contact with the surface of a roll so that as the roll is rotated about its axis, the doctor blade wipes water droplets and other contaminants (such as pitch or cellulosic fibers) from the surface of the roll. An example of a doctor blade of the aforedescribed class is shown and described in Great Britain Patent No. 908,747.
It is known that doctor blades of the aforedescribed class require frequent and costly servicing or replacement due to tip wear and are limited in their capacity to wipe water droplets from a perforated surface, such as the surface of a pick-up roll which employs a vacuum-enhanced section. If, for example, particles of grime or water droplets become lodged within the perforations of such a surface, the movement of the surface in contact with the tip of a doctor blade does not normally dislodge these droplets, and of course, if not removed from the perforations (by either the doctor blade or by the vacuum of the vacuum-enhanced section), these droplets can adversely affect the performance of the vacuum-enhanced section.
It is an object of the present invention to provide a new and improved means for cleaning a papermachine component whose surface has become grimy and wet from a paper web as the paper web moves around the surface of the component and an associated method.
Another object of the present invention is to provide such a means which removes grime and water from the surface of a papermachine component without mechanically contacting the surface of the component with a wiper tip thereby obviating any need for servicing or replacement of worn parts and circumventing the costs associated with such servicing or replacement of parts.
Still another object of the present invention is to provide such a means which is well-suited for dislodging particles of grime and water droplets from the perforations of a perforated surface of a papermachine component.
Yet another object of the present invention is to provide such a means which is uncomplicated in construction yet effective in operation.